Fix unprintable characters in some chassisid
Fix unprintable characters in some chassisid

Some switches send raw octets back, some printable.  Try to normalize
when unprintable chassis id are detected.  This is not 100%, if the hex
would be all between 20 and 80 throughout the string, then this will
fail to do the right thing.

Hopefully, the amount of times when lldp partners disagree on how to
implement LLDP-MIB will be limited.  Currently it is known than Lenovo
and Juniper switches disagree, and both of those have what would
be unprintable values in the mfg portion of the chassis id.

xcat2/confluent,whowutwut/confluent,whowutwut/confluent,jjohnson42/confluent,jjohnson42/confluent,whowutwut/confluent,jjohnson42/confluent,xcat2/confluent,xcat2/confluent,xcat2/confluent,jjohnson42/confluent,whowutwut/confluent,jjohnson42/confluent,xcat2/confluent